问题
单项选择题
龙骨安装时，弹线应清楚，位置准确，其水平允许偏差( )mm。
A．±4
B．±5
C．±4.5
D．±6
答案
参考答案：B
搜题请搜索小程序“爱下问搜题”
龙骨安装时，弹线应清楚，位置准确，其水平允许偏差( )mm。
A．±4
B．±5
C．±4.5
D．±6
参考答案：B
| Awarded the Nobel Prize for physics in 1918, German physicist Max Planck is best remembered as the originator of the quantum theory. His work helped usher in a new era in theoretical physics and revolutionized the scientific community’s understanding of atomic and subatomic processes. Planck introduced an idea that led to the quantum theory, which became the foundation of twentieth century physics. In December 1900, Planck worked out an equation that described the distribution of radiation accurately over the range of low to high frequencies. He had developed a theory which depended on a model of matter that seemed very strange at the time. The model required the emission of electromagnetic radiation in small chunks or particles. These particles were later called quantums. The energy associated with each quantum is measured by multiplying the frequency of the radiation, v, by a universal constant, h. Thus, energy, or E, equals hv. The constant, h, is known as Planck’s constant. It is now recognized as one of the fundamental constants of the world. Planck announced his findings in 1900, but it was years before the full consequences of his revolutionary quantum theory were recognized. Throughout his life, Planck made significant contributions to optics, thermodynamics and statistical mechanics, physical chemistry, among other fields. |
In which of the following fields did Max Planck NOT make a significant conla4bution
A．Optics.
B．Thermodynamics.
C．Statistical mechanics.
D．Biology.